Methylchlorosilanes are obtained in the process described by Rochow by reacting methyl chloride with elemental silicon. This reaction produces disilanes as a by-product.
In U.S. Pat. No. -A3,772,347 (issued Nov. 13, 1973, to W. H. Atwell et al., Dow Corning Corporation), a process for the cleavage of disilanes is described which comprises cleavage of the Si-Si bond in the disilane with the formation of a silicon-carbon bond and a silicon-chlorine bond in accordance with the following reaction scheme: EQU .tbd.SiSi.tbd.+R'Cl .fwdarw..tbd.SiR'+.tbd.SiCl
In these formulas, R' is an alkyl radical or hydrogen. The catalysts used are transition-metal complexes, such as phosphinepalladium complexes or finely divided platinum or palladium, which may be present on a support such as carbon.
According to Example 3 of U.S. Pat. No.-A 3,772,347, a methylchloro-silane mixture is reacted with hydrogen chloride in the presence of a phosphinepalladium complex. About 25% by weight of the methylchlorosilanes obtained contain Si-bonded hydrogen.
Therefore, it is an object of the present invention to provide a process for the cleavage of methylchlorodisilanes in which methylchlorosilanes which are free of Si-bonded hydrogen are obtained.